RAG rating
Document type
Clinical policy
Hertfordshire and West Essex ICB
Output type
Clinical Policies & Evidence-based Interventions

Mechanical Insufflation-Exsufflation (MI-E) Devices / CoughAssist

July 2022 v1.0

[This policy has been developed from the Commissioning Policies for Cough Assist developed by Walsall Clinical Commissioning Group, Swindon Clinical Commissioning Group and East Staffordshire Clinical Commissioning Group]

Funding of cough assist devices can only be obtained on a case-by-case basis as an individual funding request by the ICB.

This policy applies to patients (adults and children) who have an ineffective/weak cough due to neuromuscular disease or cervical spinal cord injury. This includes patients with conditions such as muscular dystrophy, spinal muscular atrophy, motor neurone disease and spinal cord injury. 

A mechanical insufflator-exsufflator (MI-E) device / CoughAssist assists the clearance of bronchopulmonary secretions in those patients with an ineffective cough by the use of both positive and negative pressure.  CoughAssist is a non-invasive therapy that removes secretions in patients with an ineffective ability to cough (peak cough flow <270 l/m). The CoughAssist device clears secretions by gradually applying a positive pressure to the airway, then rapidly shifting to negative pressure. The rapid shift in pressure produces a high expiratory flow, simulating a natural cough.

A multidisciplinary team should assess, manage and review the patient’s respiratory function, respiratory symptoms, non-invasive ventilation and cough effectiveness, including the person’s response to treatment. 

Funding for a MI-E device / CoughAssist will be considered for patients who meet all the following criteria and where the MDT involved in their care recommends the device will be of clinical benefit. 

Applications for funding should be submitted through an Individual Funding Request. 

Criteria For Children

CoughAssist devices are funded for paediatric patients with neuromuscular conditions in the following circumstances:

  • Children who are clinically very weak
  • Children with loss of bulbar function
  • Children who cannot co-operate with manual cough assist or air-stacking methods or these methods have not been effective


  • The patient suffers from recurrent respiratory tract infections, diagnosed and treated by a primary or secondary care doctor. Recurrent infection defined as three or more episodes over a single winter period or on-going infections greater than once every two months throughout the year. 

Criteria For Adults

1. An established diagnosis as paralytic / restrictive disorder, including but not exclusively

  • spinal cord injuries (SCI) 
  • neuromuscular diseases such as ALS 
  • Guillain-Barré Syndrome 
  • myasthenia gravis 
  • muscular dystrophy 
  • multiple sclerosis 
  • post polio 
  • kypho-scoliosis 
  • syringomyelia


2. Patient is unable to cough or clear secretions effectively with a Peak Cough Flow (PCF) less than 160L/min using Lung Volume Recruitment (LVR) with bag, Glossopharyngeal Breathing (GPB) or volume ventilator (& assisted cough manoeuvre when indicated)


3. Patient is overly fatigued when performing LVR with the resuscitation bag, GPB or volume ventilator.

Requests for MI-E / CoughAssist devices for patients who do not meet the above criteria are considered low priority and will not be routinely funded. 

Absolute Contra-Indications: 

  • Presence of haemoptysis, untreated or recent pneumothorax, bullous emphysema, nausea and emesis, severe COPD, severe asthma and recent lobectomy 
  • Increased intra cranial pressure (ICP) including ventricular drains .
  • Impaired consciousness / inability to communicate in instances where the patient does NOT have an artificial airway 

Relative Contraindications: 

  • therapy immediately following meals .
  • tachypnea 
  • history of COPD and pneumothorax 
  • large pleural effusion 
  • cervical spinal injury unclear 
  • hemodynamic instability 
  • impaired consciousness / inability to communicate where the patient has an artificial airway 

Supplemental oxygen should not be bled into the MI-E circuit. Oxygen passing through the fan system during the exsufflation phase results in a potential fire hazard.